This invention relates to electromagnetically actuated mechanical brakes, and more particularly, to such brakes arranged in interleaved stacks.
In the prior art, electromagnetically actuated mechanical brakes having multiple discs are known. These may be operated as follows: normally the discs are forced together by a spring. When current is applied, an armature is attracted toward a magnetic body, thereby compressing the spring and releasing the discs; thus allowing them to be rotated. When current is discontinued to the coil, the spring pushes the armature into engagement with the discs, forcing them together to stop the movement of the load. Thus the device holds the load with the power off.
The discs are complete circles and are generally acted upon by a centrally disposed spring and armature. This configuration is both bulky and heavy. For example, a 360 degree brake to produce 90 foot pounds of torque would have a diameter of approximately 7 inches and weigh approximately 30 pounds.
It is desirable to make such breaks lighter and more compact; so that they can fit into small mechanical devices.